Lateral, turtles

The effects of EDCs were first discovered in wildlife in the 1970s. It was found that extremely low concentration levels of these can have powerful deleterious effects on the reproduction of wildlife. Human effects were not studied until much later because most EDCs are neither mutagenic nor acutely toxic at the ambient concentrations found to have endocrine disruption effects on wildlife. It was also believed that effects on birds and turtles were not necessarily indicators of human toxicity. This, however, turned out to be exactly the case. Though toxic effects of chemicals are not always similar for different species of animals, they are just that for endocrine disruptors. The effects of EDCs on birds and amphibians are exactly analogous to those on humans. 

There was really no choice, Allen would say later. The commercial shrimp fleet was, despite their denials, driving the turtles into extinction. I knew it would be hard. But not as hard as watching a creature that has been on this earth for a hundred million years get wiped out in one generation. ... 

Our interpretation of this experiment is that if turtles receive a relatively long exposure to an olfactory cue (e.g., both in the nest and tank water), they can learn (imprint to ) that cue and at a later time show a characteristic response to that cue. In this case, the response is a specific orientation pattern to the chemical used. 

Although several inventors tried to construct submarines before the Industrial Revolution, none succeeded because they lacked an effective power source. These early submersibles, such as David Bush-neU s Turtle, built in 1776, failed because they had to rely on human power. Later, when steam power became available, inventors such as Robert Fulton designed powered submarines, but the steam engines... 

HISTORY. Calcium was among the first materials known to be essential in the diet As early as 1842, Chossat, a Frenchman, showed experimentally that pigeons developed poor bone on a diet low in calcium. When fed wheat alone, the birds died after 10 months and, on autopsy, the bones were found very much depleted. Calcium carbonate prevented the trouble. In later studies, Chossat also used chickens, rabbits, frogs, eels, lizards, and turtles. But well-controlled experiments with man were not made until recent years. 

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